The inclination of a helicopter about its transverse axis may vary greatly during the different phases of flight (hovering, climbing, cruising, etc.) due to the design. As a result, an exterior load attached to the helicopter develops an unfavorable aerodynamic characteristic.
In particular, for stable forward flight, helicopters tilt the rotor plane forward to tilt the thrust vector of the main rotor in the direction of flight. This tilting of the rotor plane may lead to tilting of the entire helicopter about the transverse axis. Mounted exterior loads in this case also tilt about the transverse axis and then are exposed to oncoming cross-flow by the surrounding air in an unfavorable manner. It may therefore be advisable to align the exterior loads in accordance with the air flow. An electromechanical load carrier may therefore be used to align an exterior load about the transverse axis in the direction of flight of the helicopter.
Furthermore, when using weapon carriers as the exterior load, the load carrier is used as an aiming unit, which makes it possible to aim the weapon at the target independently of the position of the helicopter.
In this second application, an alignment of the exterior load by the load carrier (in this case a weapon carrier) may be used for aiming. The weapons, mounted as an exterior load, can be aligned with the target in this way, independently of movements of the helicopter.
For pivoting the exterior load, a trapezoidal guide for the exterior load may be used and can be driven by a linear actuator. Disadvantages of this arrangement may include the relatively large forces acting on the actuator because the effective lever of the center of gravity can be displaced significantly by adjusting the kinematics. Another disadvantage may be the space required for the rod of a trapezoidal guide.